Best value is DIY. Occasionally there are steals to be found used on Craigslist. Otherwise, there are plenty of bargains on new subs in any price range. If you're in Europe, check out B.K. Electronics. In the US, Dayton or NXG NX-BAS-500 in the < $300 range for a small-to-mid-sized room. Hsu, Rythmik, Outlaw, or RBH / EMP Tek for 5 - 700 range. Hsu, Reaction, or Power Sound above that... It really depends on your room size, space limitations, need for WAF, and what you can afford. Pick your budget and your compromises, and don't short change a large room with an inadequate sub regardless of bargain.
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